This invention is in the field of cleaning compositions. More specifically, this invention relates to cleaning compositions including a rubber solvent, a degreaser, and a diluent. The compositions can be used to clean oil, grease, tar, rubber, organic matter, particulate matter and other debris from soiled surfaces
Some environments generate a tough combination of dirt, grime, soil, and debris that is very difficult to clean effectively with only one cleaner. One example of such an extreme environment is the vehicle race track, e.g., auto speedway, truck speedway, or the like. In the course of a race, windshields are splattered both with oils (e.g., motor oils and gear oils) and with rubber bits thrown from race tires that erode during racing. Dirty windshields obscure the driver""s visibility, impairing the safety of all race participants. Accordingly, it is common practice to try and clean race vehicle windshields during pit stops.
Cleaning a race vehicle windshield at a pit stop is not a simple matter, because this use imposes many stringent demands on a cleaner. In addition to being able to remove oils and rubber and other soil on the windshield, the cleaning agent must act to remove this grime very fast, i.e., within the time constraints of the pit stop. The cleaner also must be easy to remove quickly from the surface. Desirably, therefore, the cleaner must not only act fast, but also evaporate at a quick enough rate so that the time spent wiping the windshield with a clean cloth, squeegee, or the like, will be at a minimum. While quick cleaning action is important, this must also be balanced against residence time. The cleaner components must evaporate at a slow enough rate so that the cleaner has a long enough contact time with the soiled surface to remove the soils. Ideally, the cleaner also should go on and come off without requiring any rinsing with water or any other rinse agent.
Besides being fast and simple to use, the cleaner must be compatible with the race vehicle itself. Importantly, the cleaner must leave no residue behind that might obscure visibility through the windshield. The cleaner also must not damage the LEXAN polycarbonate material that forms the windshield or the silicone sealant around the edge of the windshield. The cleaner must also be compatible with MYLAR polyester, because a clear plastic sheet, often made of MYLAR polyester and called a xe2x80x9ctear-awayxe2x80x9d, often is used to cover the windshield. The xe2x80x9ctear-awayxe2x80x9d is used to dampen impacts from particulate matter during the race and can be removed quickly during a pit stop when the sheet becomes so damaged that it obscures the race vehicle driver""s view. Cleaners splashed across a windshield inevitably will contact the race vehicle body, too. Therefore, the cleaner must not damage the race vehicle""s body paint. The cleaner also should provide good cleaning performance over a wide temperature range. For example, it would be very desirable to have a cleaner that provides good cleaning performance at temperatures ranging from 25xc2x0 F. (xe2x88x924xc2x0 C.) to 140xc2x0 F. (60xc2x0 C.).
Race vehicle bodies and the walls at racetracks need to be cleaned, too. These surfaces also are splattered with the same soils as the windshield, including oils and rubber. Also, race vehicle bodies and/or race track walls may be smeared with rubber from the tires of other race vehicles that sideswipe such surfaces during races. For these surfaces, in addition to being able to remove oils and rubber under the stringent conditions described above, the cleaning agent must not unduly damage the inks or the backings of the promotional decals or other graphics that are affixed to the vehicle""s body or the racetrack walls.
The racetrack, of course, is just one example of an environment in which oils and rubber collectively challenge a cleaner. There are many others, too. For example,
automobiles, trucks, motorcycles, and the like also get splattered with oils, tar, rubber, bugs, and the like during the course of ordinary street driving. Industrial equipment, industrial floors which have been traversed and marked by tires, engines, motors, railways, railway cars, and the like may also suffer from such grime.
What is needed is a universal cleaner that has the power to clean oil, tar, rubber, bug residue, and other soils over a wide temperature range, yet will not damage metal, many paints, many inks, ceramic, wood, concrete, many plastics and/or the like.
The present invention provides an extremely versatile cleaning composition that has tremendous cleaning power, yet is compatible with many surfaces. For example, the cleaning composition easily cleans oil, grease, tar, and rubber from soiled surfaces, but does not damage metals, vehicle paints, concrete, plastics (such as polycarbonate, polyester and silicone sealants), wood, ceramic, and the like. The ability of the cleaner to clean such tough soils while still being gentle enough not to harm a wide range of surfaces is very surprising, since many conventional cleaners having comparable cleaning power will damage plastics and other surfaces. The cleaner also works fast and leaves no residue. It can be applied and wiped off, or otherwise removed, without delay after being applied. It will also clean effectively over a wide temperature range, including temperatures ranging from 25xc2x0 F. (xe2x88x924xc2x0 C.) to 140xc2x0 F. (60xc2x0 C.).
Accordingly, it can be appreciated that the cleaner is particularly suitable for use in the racetrack environment. For example, it can be used to clean windshields very quickly during a pit stop. When a vehicle pulls in for a pit stop, a pit crew member can splash, pour, spray, or otherwise cause the cleaner to contact the windshield. Soil on the windshield will be quickly dissolved or otherwise loosened from the window surface. Without delay, the crew member can then use a cloth, sponge, squeegee or the like to immediately remove the cleaner and the loosened soil. In only a few seconds, the windshield is clean and ready for more racing action. Of course, the vehicle body may also be cleaned just as quickly, if desired. After the race, the other surfaces of the racetrack facility, e.g., walls, bleachers, pavement, and the like, may also be easily cleaned.
Race vehicle teams also have practice sessions and/or testing sessions before races and at other times. The vehicles get dirty in these sessions, too. The cleaner can also be used to clean the vehicles after these sessions, as well as after a race.
In one aspect, the present invention relates to a water-restricted cleaning composition, comprising an oil solubilizing amount of a degreaser; a rubber solubilizing amount of a rubber solvent; and a polar, organic diluent. In preferred embodiments, the degreaser comprises a glycol ether, the rubber solvent comprises a nonaromatic (e.g., aliphatic and/or alicyclic) naphtha, and the diluent comprises an alcohol, preferably a C2 to C5 alcohol. For purposes of the present invention, an alcohol containing a sufficiently small quantity of water such that the composition is a single phase (e.g., alcohol with an azeotropic amount of water or less) shall be deemed to be a polar, organic diluent for purposes of the present invention.
In another aspect, the present invention relates to a method of cleaning a surface, comprising the steps of causing the surface to contact a water-restricted cleaning composition comprising an oil solubilizing amount of a degreaser, a rubber solubilizing amount of a rubber solvent, and a polar, organic diluent. In preferred embodiments, the degreaser comprises a glycol ether, the rubber solvent comprises a nonaromatic naphtha, and the diluent comprises an alcohol, preferably a C2 to C5 alcohol.
In another aspect, the present invention relates to a method of making a cleaning composition, comprising the step of combining ingredients comprising an oil solubilizing amount of a degreaser, a rubber solubilizing amount of a rubber solvent, and a polar, organic diluent.
The embodiments of the present invention described below are not intended to be exhaustive or to limit the invention to the precise forms disclosed in the following detailed description. Rather the embodiments are chosen and described so that others skilled in the art may appreciate and understand the principles and practices of the present invention.
Cleaning compositions of the present invention generally include one or more degreasers, one or more rubber solvents, and one or more polar, organic diluents. In the practice of the present invention, a degreaser is a fluid, slurry, or the like that is capable of solubilizing grease, oil, hydrocarbons, and the like. Preferred degreasers of the present invention satisfy the Oil Solubility Test. According to this test, two or three drops of 20W-50 racing motor oil are dropped into 2 ounces (59 ml) of the degreaser at room temperature. The degreaser is deemed to solubilize the oil and satisfy the test if the oil dissolves in the degreaser, optionally with stirring, to form a single phase mixture within no more than 10 to 20 seconds, preferably no more than 5 to 10 seconds.
Representative examples of suitable degreasers include a wide variety of organic solvents and generally include materials such as ketones, amines, esters, tetrahydrofuran or other heterocycles, alcohols, ethers, glycol ethers, combinations of these, and the like. Of these, one or more glycol ethers are particularly preferred for a variety of reasons. Firstly, glycol ethers have excellent oil dissolving capabilities. These compounds solubilize oil very quickly. It is believed that glycol ethers are such excellent solvents because they combine the solvent characteristics of both alcohols and ethers. Additionally, glycol ethers tend to form compatible, single phase mixtures with the other components of the cleaning composition, significantly without unduly compromising the cleaning power of those other ingredients. The volatility of glycol ethers is also in a suitable regime so that cleaning compositions incorporating these materials dry at a rate that is not too fast or too slow. Glycols ethers also are compatible with the race vehicle environment. When included as a constituent of the present invention, these compounds do not damage LEXAN polycarbonate brand polycarbonate used as windshield components, MYLAR polyester, the silicone seal of such windshields, the paint finish on the vehicles, or many decals.
Glycol ethers may be made by reacting alcohols and ethylene oxide in accordance with conventional methods. Glycol ethers also are widely available from a number of commercial sources. Specific examples include propylene glycol n-butyl ether (Dow Chemical Company), propylene glycol n-propyl ether (Dow Chemical Company), diethylene glycol monobutyl ether (Eastman Chemical Co.), ethylene glycol monobutyl ether (Eastman Chemical Co.), dipropylene glycol methyl ether, (Dow Chemical Company) propylene glycol methyl ether (Dow Chemical Company) combinations of these, and the like.
The cleaning composition of the present invention generally includes a sufficient amount of one or more degreasers such that the composition can satisfy the Oil Solubility Test described above. However, above a certain level, adding too much degreaser offers little additional benefit beyond that provided by lesser amounts. The enhanced cleaning power might also be detrimental to some inks and paints. The composition also might not be as user-friendly. Accordingly, preferred cleaning compositions of the present invention include 1 to 20, preferably 3 to 15, more preferably 5 to 10 parts by weight of the degreaser per 5 to 70, preferably 20 to 60, more preferably 35 to 50 parts by weight of the rubber solvent. A particularly preferred composition includes 6% to 10% by volume of at least one glycol ether as the degreaser.
The rubber solvent is a material that is capable of at least partially solubilizing rubber. The presence of the rubber solvent allows the cleaning composition to easily remove bits of rubber that may be stuck to surfaces such as race vehicle windshields, race vehicle bodies, race track walls, industrial floors, motorcycle windshields, and the like. This component is especially suitable for rapidly removing tire bits from race vehicle windshields during a pit stop.
A wide variety of rubber solvents are known and may be advantageously incorporated into cleaning compositions of the present invention. Preferred rubber solvents belong to the class of hydrocarbon solvents and may be aliphatic, aromatic, straight chain, branched, linear, and/or cyclic. The suitable hydrocarbon solvents may comprise one or more hetero atoms and be substituted or unsubstituted. Representative examples of rubber solvents include one or more of toluene, benzene, xylene, C5 to C15 paraffins, cycloparaffins, an olefin, acetylene polymers, terpene polymers, isoprene polymers, turpentine, petroleum products such as gasoline, kerosene, petroleum distillate, naphtha, mineral spirits, and the like; and natural and/or synthetic hydrocarbons and/or oils such as mineral oil, vegetable oil, animal oil, essential oil, edible oils, combinations of these, and the like. Specific oils include fish oil, sperm oil, fish-liver oil, corn oil, safflower oil, soybean oil, cottonseed oil, palm oil, coconut oil; combinations of these, and the like.
Although embodiments may be aromatic or aliphatic, aromatic rubber solvents tend to damage polycarbonate and other plastic surfaces. Accordingly, nonaromatic rubber solvents are preferred in those embodiments of the present invention to be used for cleaning polycarbonate or other plastic surfaces, e.g., race vehicle windshields. In this regard, a naphtha or naphtha derivative (collectively referred to as xe2x80x9cnaphthaxe2x80x9d herein) is preferred.
Rubber solvents suitable in the practice of the present invention are widely available from a number of commercial sources. Representative examples of these include Exxon 2024 Naphtha (Exxon Chemical Company) Exxon Exxsol D115/145 Naphtha (Exxon Chemical Company), Exxon Isopar E fluid (Exxon Chemical Company), VMandP naphtha HT (Shell Chemical Company), Cypar-7 hydrocarbon solvent (Shell Chemical Company), Special Naphtholite 66/3 hydrocarbon solvent (Citgo Petroleum Corporation), Sol 340 HT hydrocarbon solvent (Shell Chemical Company), Soltrol 10 hydrocarbon solvent (Philips Chemical Company), Solvo-Kleen hydrocarbon solvent (NCH Corporation), Soltrol 70 (Phillips Chemical Company), combinations thereof, and the like.
The cleaning composition includes enough of the rubber solvent so that the composition has the desired level of rubber removing capabilities, but not so much that the cleaning composition leaves an undesirable residue on the surface being cleaned. Preferred cleaning compositions include 5 to 70, preferably 20 to 60, more preferably 35 to 50 parts by weight of the rubber solvent per 1 to 20 preferably 3 to 15, preferably 5 to 10 parts by weight of the degreaser.
The cleaning compositions also include one or more organic diluents. In the practice of the present invention, the diluent may be active, latent, or inactive. Active means that the diluent is a strong solvent for the soil being cleaned. Latent means that the diluent functions as an active solvent in the presence of one or both of the degreaser and/or rubber solvent. Inactive means that the diluent is a nonsolvent for the particular soil at issue, but may be present to help control viscosity, evaporation rate, or the like. As general guidelines, using 5 to 70, preferably 20 to 60, more preferably 35 to 50 parts by weight of the diluent is advantageously used per 5 to 70, preferably 20 to 60, more preferably 35 to 50 parts by weight of the rubber solvent.
The preferred organic diluent may be any solvent or combination of solvents that is capable of forming single phase mixtures with the rubber solvent and the degreaser. Preferred diluents comprise one or more nonaqueous, polar solvents. These preferred diluents include, for example, alcohols such as ethanol (typically denatured for this use), isopropyl alcohol (preferably at least 99% pure), combinations of these, and the like. Alcohols evaporate cleanly, are polar, are excellent wetting agents, and are typically latent or active solvents. Alcohols are also excellent carriers of carbon black, which is typically a constituent of the rubber residues that might be cleaned with the present invention. Accordingly, an alcohol may enhance the rubber cleaning performance of the cleaning composition. C2 to C5 alcohols are preferred, of which isopropyl alcohol and ethanol are most preferred. Isopropyl alcohol (IPA) provides exceptional cleaning performance, but may have a tendency to degrade some brands of decals used on race vehicle bodies. Ethanol is much more compatible with such decals and is therefore desirably used in applications in which the cleaning composition may come into contact with such decals. A combination of isopropanol and ethanol may be useful to obtain a good balance between optimum cleaning power and compatibility with decals. In such embodiments, the weight ratio of isopropanol to ethanol may be in the range from 1:19 to 19:1, preferably 1:4 to 4:1.
In addition to the degreaser, the rubber solvent, and the diluent, cleaning compositions may also include one or more additives that enhance the stability, performance, and/or handling of the cleaning composition. For example, other additives that might be used include antistatic agents, foaming agents, antioxidants, anticorrosion agents, fungicides, bactericides, fillers, pigments, combinations of these, and the like. If any of these are used, they may be used in accordance with conventional practices.
Cleaning compositions of the present invention are preferably water-restricted. It has been found that the presence of too much water not only may have a destabilizing effect upon the cleaning composition itself, but also may tend to impair cleaning performance. Accordingly, xe2x80x9cwater restrictedxe2x80x9d in the practice of the present invention means that the cleaning composition includes a low enough content of water such that the cleaning composition is a single phase at room temperature, and more preferably, remains a single phase at temperatures as low as 31xc2x0 F. (0xc2x0 C.). Preferred compositions contain less that 5%, preferably less than 1%, and more preferably less than 0.5% water. For purposes of determining water content, water that is in azeotropic combination with an alcohol or other constituent shall be deemed to be part of the aqueous content of the composition.
Preferred cleaning compositions of the present invention are also substantially free of surfactants, particularly in instances in which the cleaning composition is to be used to clean race vehicle windshields during the course of a race. Compositions that include surfactants have a tendency to leave a residue on the surface being cleaned, and this residue is relatively difficult to remove quickly in the timeframe of the typical pit stop. Such a residue is undesirable since it can impair the driver""s visibility, posing a danger not only to the driver but to other racers, support crews, officials, and bystanders.
Cleaning compositions of the present invention are extremely easy to make and use. According to one approach of making the composition, the ingredients are combined in the desired proportions in a vessel and then stirred until the mixture is homogeneous. The ingredients can be combined in a batch or a continuous process. The mixture has a long shelf life and can be stored in a suitable storage container for very long periods of time. Alternatively, the mixture can be used relatively soon after it has been made.
To clean a soiled surface, the cleaning composition can be poured directly onto the surface, applied by cloth or sponge or other implement, sprayed, or the like. The cleaning composition will quickly loosen and/or dissolve oils, greases, rubber, tar, organic residues, particulate matter, and the like. If desired, the composition can be used to scrub the surface to remove especially stubborn soil, if desired. The composition and soil are then removed from the surface with a clean cloth, sponge, squeegee, or the like. The cleaning composition is particularly useful for cleaning race vehicle windshields, where fast cleaning action is paramount.
The present invention will now be further described with reference to the following examples.